The present invention relates to a storage system comprising at least two parallel racks with storage positions for products disposed beside and above each other and with an aisle extending between respective sets of at least two adjacent racks, through which shuttles can move forward and backward over respective guides parallel to the racks on a multitude of superposed levels for placing products in the storage positions and/or removing products from the storage positions, wherein the storage system further comprises a maintenance cart which can be moved through an aisle.
The present invention further relates to a method for carrying out maintenance or the like on a shuttle in such a storage system.
U.S. Pat. No. 7,591,630 discloses a storage system in which products are stored in containers such as bins in racks disposed parallel to each other. Autonomously operating shuttles can move through aisles between the racks in the storage system. The shuttles are for that purpose each provided with their own driving system, including a battery, and are capable of autonomously storing a container with one or more products in a desired storage position or collecting it therefrom and transport it to a collecting location on the basis of wirelessly transmitted commands from a central storage system. The shuttles can furthermore move from one aisle to another aisle and also from one level to another level.
When a shuttle comes to a standstill within the storage system in use, an individual, such as a maintenance mechanic, must localise and approach the shuttle in question. To approach the shuttle in question is, platforms are provided in the storage system according to U.S. Pat. No. 7,591,630, over which the shuttles can move at every level. Said platforms can each be swung to one side. This makes it possible to fold up platforms of respective levels from a position located one or a number of levels above the shuttle in question and to repeat this action until a maintenance mechanic has reached the shuttle and can carry out maintenance or repairs from the upper side of the shuttle. This is a laborious and complex process, whilst in addition the shuttle is only accessible to a limited extent to the maintenance mechanic. In the above-mentioned known storage system and also in particular in storage systems that are not provided with the aforesaid folding platforms and wherein the maintenance mechanic must make his way through the aisles to approach a shuttle, a large part of the storage system must be shut down for the sake of the safety of the maintenance mechanic during the time the mechanic is present within the system. However, in view of the large number shuttles that move autonomously through the storage system on various levels, the speed at which the shuttles move, the lack of possibilities for the maintenance mechanic to get out of the way in the aisles and the wireless control of the autonomously operating shuttles, it remains risky for the maintenance mechanic to enter the aisles, as it is very difficult to guarantee that the relevant part of the system has actually been shut down completely and no shuttles will pass through the aisle in question. In addition, shutting down a major part of the storage system is undesirable for efficiency reasons.
US 2012/0185080 discloses a storage system as described in the introduction. The possibility of using a maintenance cart is suggested in general terms in said publication, special details thereof are not revealed.